A baker is using a cookie recipe that call for 2 ¼ cups of flour to yield 36 cookies. How much flour will the baker need to make 90 cookies using the same recipe?
A. 6 ¾ cups
B. 5 5/8 cups
C. 10 1/8 cups
D. 4 ¾ cups
We are asked to find the number of cups of flour that will be used to make 90 cookies.
Letting x be the number of cups of flour and setting the proportion equation with number of cookies on numerator and number of cups of flour on the denominator. We have
Solve the value of x by cross-multiplying
We convert the mixed fraction into improper fraction in order to carry out multiplication
\(x =\ \frac{9}{4}\ cups\ *\ 90\ cookies\ *\ \frac{1}{36}\ cookies\)
The number of cups of flour needed to make 90 cookies is 5.625 cups, which is equal to 5 5/8 cups(Choice B).
Therefore, the Correct Answer is B.